This section provides background information related to the present disclosure, which is not necessarily prior art.
Internal combustion engines (“ICEs”) typically include a combustion chamber, an intake and exhaust port, a compression device, a fuel delivery system, and an ignition device. ICEs place the ignition device into constant contact with the combustible mixture of air and fuel and control the ignition of that mixture by intermittent activation of the ignition device. For example, intermittent operation of a spark plug, activated by a high voltage pulse to produce a plasma flame kernel. However, in order to achieve higher fuel efficiency, the compression ratios of ICEs are growing higher, and the air-fuel mixtures are becoming leaner. This requires ignition devices such as spark plugs to use higher voltages for consistent combustion.
Furthermore, the ignition devices are exposed to the high ranges of pressures, temperatures, and chemical mixtures that exist in the combustion chamber during the entire engine cycle. This exposure can lead to degradation of the ignition device, including buildup of soot, which can result in inconsistent combustion and loss of fuel economy and power. Additionally, ignition devices in ICEs utilizing compressed natural gas (“CNG”) as the fuel tend to build up soot more quickly than ICEs operating on traditional fuels, such as gasoline, for example. This additional buildup can require more frequent maintenance, often making CNG ICEs impractical or too costly for certain applications.
The geometry and operation of sparkplugs also makes controlling the propagation of the flame front difficult. This can lead to premature flameout resulting in inconsistent combustion, and loss of fuel economy and power.